Study Guide Pesachim 19 Today’s daf is sponsored by Neil Green in honor of Sabina. You are an inspiration in your leadership of our temple education committee and in your teaching of children in the school. You live the Torah you teach. I am so grateful that you are learning Daf Yomi with Hadran with me! Rava says that Rabbi Yosi doesn't agree with Rabbi Akiva and Rabbi Akiva doesn't agree with Rabbi Yosi so how did we say before that Rabbi Yosi's opinion is derived from Rabbi Akiva. How do we know that each doesn't hold like the other? The gemara brings another halacha that Rabbi Chanina Sgan HaKohanim testified about. A needle found inside a slaughtered animal will not pass on impurity to the hands of the slaughterer or the knife but it makes the meat impure. What exactly is the case? What is the doubt referring to?